Dang..that's a sweet looking boat!

prolong idling.
 

MSD ign will make them fire at idle. mine have a lite roll at idle but don't load up. nice boat good luck with it

I'd def. agree with both....Have the carbs cleaned (maybe a quick little re-build) and put some MSD on there. Ours have MSD and theres no probs at idle. Not really any lobe either (you can adjust it to lobe more to none at the carb). I do have problems with them wanting to die when put into gear but that's a carb prob too. I have holley dominators on there with the large jets. It just needs to be adjusted.

You can clean up the carburetors, and adjust the idle circuits on them so they don't load up while you're idling.